Wind power is considered one of the cleanest, most environmentally friendly energy sources presently available, and wind turbines have gained increased attention in this regard. A modern wind turbine typically includes a tower, a generator, a gearbox, a nacelle, and a rotor. The rotor typically includes a rotatable hub having one or more rotor blades attached thereto. A pitch bearing is typically configured operably between the hub and the rotor blade to allow for rotation about a pitch axis. The rotor blades capture kinetic energy of wind using known airfoil principles. The rotor blades transmit the kinetic energy in the form of rotational energy so as to turn a shaft coupling the rotor blades to a gearbox, or if a gearbox is not used, directly to the generator. The generator then converts the mechanical energy to electrical energy that may be deployed to a utility grid.
As the size of rotor blades increase, the noise produced by the rotor blades may also increase. As such, in certain instances, various blade add-on components may be attached to the rotor blades to assist with reducing noise generated thereby. More specifically, certain blade add-on components may be attached adjacent to the trailing edges of the rotor blades. Such blade add-on components may, for example, include serrations attached to the trailing edges of the rotor blades. Traditional serrations, however, can suffer from a high-frequency noise increase due to the side edge vortices created by the pressure imbalance on both sides of the serration.
Accordingly, the present disclosure is directed to noise reducers that eliminate the noise-generating side edges of conventional serrations to address the aforementioned issues. In addition, the noise reducers of the present disclosure are configured to modify the scattering of pressure fluctuations into sound waves.